Screen shot showing faulty display: https://drive.google.com/open?id=1twOdSMG8mIC2lHHAmoA2khucXSpXn-Lq
Running from a terminal gives: $ thunderbird (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_ref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_unref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_ref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_unref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_ref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_unref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_ref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_unref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_ref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_unref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_ref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_unref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_ref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_unref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_ref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_unref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_ref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_unref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_ref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_unref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_ref: assertion 'object->ref_count > 0' failed (thunderbird:27089): GLib-GObject-CRITICAL **: g_object_unref: assertion 'object->ref_count > 0' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed (thunderbird:27089): Gtk-CRITICAL **: gtk_icon_theme_lookup_icon_for_scale: assertion 'scale >= 1' failed
